An accelerometer sensor is one of commonly used motion sensors and is used in various solutions, such as for a pedometer, screen rotation, automatic brightness, and free fall detection. Algorithms in all such cases require accelerometer data to be polled not only at 100 Hz, but also at 5 Hz, 16 HZ, and 50 Hz.
A device having a sensor operates using the following two methods.
First, a sensor is connected to an application processor (AP). The AP is in a wake up state to receive data and periodically polls the sensor.
Second, a sensor is connected to a microcontroller (MCU, i.e., a sensor hub). An AP may sleep and the may be sleepwalking. Processing may occur in the MCU, and the MCU may wake up the AP when necessary. Here, the MCU periodically polls the sensor.
A major disadvantage of such a polling method is that a system requires uninterrupted polling of accelerometer data either from an AP or from an MCU. As a result, there is a possibility that battery performance may largely deteriorate because such a polling method requires a huge amount of processing and continuous polling with respect to a sensor and the sensor needs to operate in a normal mode. Latency in data is another big problem in an MCU-based method. Accelerometer data may be available to an upper layer through a polling mechanism and is used in the upper layer for decision making for all algorithms. Due to the polling mechanism and complex decision making processes accompanied by mathematical operations or signal processing, sluggish behavior may be generated, and thus it may be impossible to receive real-time responses.
In existing architecture, accelerometer data is transmitted to an application layer by using a polling mechanism. Such an operation is intensive for a central processing unit (CPU), and thus a data receiving rate is reduced. Most applications access data by using the polling mechanism. In other words, the data is processed in an uppermost layer and then necessary actions to be taken are determined according to algorithms. Accordingly, a possibility of a high-speed response is reduced in cases where a fall is detected. Due to the polling mechanism, CPU million instnictions per second (MIPS) are wasted and thus power consumption is increased.
Accordingly, there is a need for a method for a high-speed dynamic response of a smart device, which provides an instant alert and does not require a polling mechanism.
The above information is presented as background information only to assist with an understanding of the present disclosure. No determination has been made, and no assertion is made, as to whether any of the above might be applicable as prior art with regard to the present disclosure.